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Jury-rig, jerry-rig, jerry-built

A little-used definition of jury is intended or designated for temporary use. It’s a nautical term of unknown origin, and in its early use it usually appeared in the phrase jury mast,referring to a temporary mast put up to replace one that has been lost.1 This is the source of the verb jury-rig, meaning to assemble for temporary use, and its derivative adjective jury-rigged.

Jerry-rig is a variant spelling of jury-rig. One could call it incorrect because it entered the language several centuries after jury-rig and is obviously derived from a misspelling of the original, but it is widely used and is accepted by some dictionaries.

It would be easier to dismiss jerry-rig as incorrect if we didn’t have the separate adjective jerry-built, which means built of bad materials. Jerry-built may or may not be etymologically related to jury-rig (its origins are mysterious), but all major dictionaries agree that jerry is the correct spelling in this case.

Examples

[A]bout 45 tonnes of contaminated water had been found near a desalination unit that is part of the plant’s jury-rigged emergency cooling system. [Financial Times]

The passengers jerry-rigged the ship … by hoisting the cracked beam with a “great iron screw.” [The Salem News]

So if the Big 12 needs OU to play on Thanksgiving Weekend the week before Bedlam … it needs to jerry-rig some kind of rivalry that makes people care. [NewsOK]

The Libyan rebels displayed tremendous ingenuity in repairing, jury-rigging and improvising weapons of all kinds. [Field and Stream]

also, in WW2, fuel was supplied in jerry-cans. then, especially in the South Pacific, the cans were often used for many other purposes, especially “jerry-built” constructions. I wonder if this encouraged the movement from Jury-built to jerry-built.

It is my understanding that “Jerry-rigged” was what the Allied Troops in WW2 called it when they saw instances where the Germans (Jerry’s) had rigged their equipment to “work”, presumably because of a lack of materials after supply lines had been disrupted.